The Penn's Grove record., 1887-08-27
for infants and children.
SCIENTIFIC.

SCIENTIFIC.
Paper manufacturers are now resort
ing TO an ingenious process for the pro-
duction of water-marked papers, a pro-
cess involving the production of such
water lines after the paper has been
printed or calendered. The design or
device to be produced IS drawn on thin
paper and pasted on TO cardboard, say
of one inch thickness. The design is
next cut out and pasted on to a stout
cardboard and covered with a thin
sheet of paper, and on the plate or re-
lief thus produced being passed through
a calender, together with the paper to
be marked, the effect desired is pro.
dUced, and the relief or plate may be
used repeatedly.
a new novelty hunting knife has
made its appearance. the special feature
of which is the in which the
blade is connected with the handle and
opens. In operating this knife it is
held point downward, then by moving
the latch which holds the blade the
blade drops out to its full length and is
Iiltu III ullJ lOGhOhs Al NAcohhAB bAN
knife the operation is reversed-the
point turned up and the latch drawn
back when the blade drops in, and the
latch being released the blade Is Sc
curely closed, keeping the blade In and
excluding dirt from the knife.
Tie discovery of a new gas is a rare
and important event to chemists. Such
a discovery has been announced In Ger
many by DR.. Theodor Curtius, who has
succeeded in preparing the long. sought
hydrlde OF nitrogen, amidogen, diamide
or hydrazine, as 1t is variously called.
This remarkable body, which has hith-
erto bafled all attempts at isolation, is
now shown to be a gas, perfectly stable
up to a very high temperature, of a pc
culiar odor, differing from that OF am
monia, exceedingly soluble in water
and of basic properties. In composition
it IS nearly identical with ammonia,
both being compounds of nitrogen and
hydrogen.
TIE nitrate of lead is the cheapest
disinfectant known that ful6lls its in
tent. 1t is made by dissolving half a
dram of nitrate of lead in a pint of
boiling water, then dissolve two drains
of common salt in eight or ten quarts
of water. When both are thoroughly
dissolved pour the two mixtures to-
gether, and when the sediment has
settled you have a pail of clear fluid
which is the saturated solution OF the
chloride of lead. a pound of the nitrate
will make several barrels of the liquid.
We thus describe Theoretically sealed
batteries. The cell is made of ebonite,
and is closed by an ebonite lid with a
washer of soft india-rubber. The upper
part Of the cell tHf--n+a several
divisions, in WHICH are placed tne- Car
bons and Zines; the lower part contains
the exciting fluid, The battery is put
into action by reversing it. In the ebo-
mite lid are apertures closed by thin
sheets of india-rubber. These al
low Of the expansion of the gas
produced in the battery. without
any risk of damage to the ebonite cell,
and without the acid being forced up
through the vent as is the case in other
Dramatically sealed batteries.
4 nc10 material called nemortolythe
has been introduced in the manufacture
of paper. 1t is said to be far superior
to plaster or kaolin. 1t contains from
90 to SO per cent. of silicate of magne-
STA, and resembles in its composition
asbestos and other s~ilIcates of magne-
sia. 1t is distinguished by its great
purity and its freedom from peroxide of
iron, from sulphur and from lime. IL
is of a brilliant white color, and paper
from it takes a very high glaze. 1t is
hbrous, and is therefore susceptible Of
telling. Those who have used it speak
very highly Of it.
A netU kind of scale consists of a SIM
point, supported by a standard about
eighteen inches in height. There are
two scales in the balance arm; M de-
notes the weight and the total cost of
the article weighed, and the other the
unit OF price, which is designated by a
sliding weight. From this sliding
weight IS suspended the scoop or slab
to contain the article to be weighed.
BY this scale the total cost of an article
at any point Is given Immediately upon
weighing 1t.
The fifteen great American inventions
OF worldwide adoption are: l, The
c~otton-gin; 2, the planing-machine; 8, !
the grass mower and reaper; 4, the
rotary printing press; 8. navigation by
steam; 6, the hot-alr engine; 7, the
sewing machine; 8. the India rubber in
dustry; 8, the machine manufacture OF
h~orseshoes; 10, the sand-blast for cary
ms; IL, the gauge leather; II, the grain
elevator; IL, artificial ice-making on a
large scale; IA, the electric magnet and
Its practical application; 10, the tele-
phone. !
Ebony is now initiated on wood by
simply painting with d l per cent. solu-
tion of sulphate of copper, and. on this
becoming dry, painting the wood Ovtr
with a liquid consisting ofequal weights
OF anlllne, hydrochloride and spirits of
wine; the effect of the blue vitriol Is to
act on the ~aniline, and form nigrosin, a
black which cannot be effected by acids
or alkalies. To this a lustre can he
added by coating the surface with SIM
pie copal varnish.
For a quick filter take q clear piece
of chamois skin, free from thin places,
cut 1t OF the desired length, wash in a
weak solution of Sal soda or any alkali
to remove the grease, and rinse thor
oughly In cold water before using.
Tlnctures, elixlrs, sirups, ard even
mucllages are filtered rapidly. A pint
OF the thickest strip will run through
in four or FIVE minutes. BY washing
thoroughly after each time or using 1t
will last a long time.
Eren the BLACKSMITH need not have
callous OF erackSd hands, If be will wash
them In soft water in which borax has
been dissolved two ounces to twelve
quarts OF water). rubbing them well
with brown soap and fine sand. The
washing must be thorough.